P-100: Interpretation of Mice Vaginal Smears to Determine Estrous Cycle Based on Uterine and Ovary Tissue Sections

Background: Rodents with short reproductive cycle length are the best model for investigation of physiology and molecular aspects of reproductive biology. This study aimed to establish a correlation between histological changes of uterus and ovaries with the vaginal smear. Materials and Methods: 6-8 weeks old virgin Female NMRI mice were submitted to the vaginal smear collection and observed using the light microscope. Histological sections were prepared from their uterus and ovaries simultaneously. Correlation analysis between epithelial and stromal parameters of uterine and ovaries were performed, in parallel, these parameters were analyzed in relation to the vaginal smear classification of estrous stages. Results: Vaginal smears of 4 stages of mouse estrous cycles (proestrus, estrus, metestrus, and diestrus) can predict many concurrent cellular and stromal events in the mouse uterus and ovaries. Conclusion: Vaginal smear is a reliable method to demonstrate the changes in reproductive organs of mouse during the estrous cycle.